• Title/Summary/Keyword: quality trend

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The Quality Assessment of Reporting of Intervention Studies on Sasang Constitutional Diet (사상체질 식이 중재연구 보고에 대한 질 평가)

  • Kim, Ji Hwan;Lee, Ju Ah
    • Journal of Sasang Constitutional Medicine
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    • v.32 no.4
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    • pp.11-28
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    • 2020
  • Objectives The purpose of this study was to evaluate quality of reporting of intervention studies on Sasang Constitutional diet (SCD) based on the Consolidated Standards for Reporting of Trials (CONSORT) and Transparent Reporting of Evaluations with Nonrandomized Designs (TREND) statements. Methods We searched for Randomized controlled trials (RCT) and Non randomized studies for intervention (NRSI) on SCD in 4 databases and other sources, selected them by the inclusion criteria, and then evaluated quality of reporting of them. Results 1. A total of 10 studies (1 RCT and 9 NRSI) from 1999 to 2006 were selected and evaluated. The detailed items of up to 78%, at least 40%, and median value of 59% in the CONSORT and TREND statements were not reported. 2. One RCT was reporting 4 (11%) sufficiently, and 4 (11%) insufficiently among the 37 detailed items in the CONSORT statement while it was not reporting 29 (78%) items. 3. Nine NRSI were reporting 7 (12%) items sufficiently, and 2 (3%) items insufficiently among the 58 detailed items in the TREND statement while they were not reporting 15 (26%) items. Twenty (34%) items in the TREND statement were reported in some papers but not in more than half. Conclusions The quality of reporting of intervention studies on SCD has been assessed to be generally low. Subsequent researchers are recommended to select an appropriate statement for research design, and use it as a checklist from the time of designing the study to the time of reporting.

A Trend on Quality Transformation of Waterproof Agent and Admixture of Cement for Concrete Surface Treatment (콘크리트 표면처리용 시멘트 액체방수제의 품질동향)

  • 최은수;김영근;박헌일;정순자
    • Proceedings of the Korea Concrete Institute Conference
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    • 2003.11a
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    • pp.557-560
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    • 2003
  • This study deals with the method of test for waterproof agent and admixture of cement, and especially, the effect on bond strength between waterproofing layer and mortar or concrete substrate in building construction. Quality of that has been managed according to it of construction standard manual, housing construction manual, 건, and Q until performance of that is specified by law as KS F 4923. Therefore this study focus on the quality and trend for a fatty system and PCM(Polymer Cement Mortar)

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A Study of Measuring Service Customer's Qualitative Quality Cost and Its Influence to Value Perception (서비스 고객의 정성적 품질비용 측정 및 가치지각에의 영향력에 관한 연구)

  • 서창적;권영훈
    • Journal of Korean Society for Quality Management
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    • v.29 no.1
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    • pp.61-84
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    • 2001
  • The problem of trend change in the failure rate is great interest in the reliability and survival analysis. In this paper we develop a test statistic for testing whether or not the failure rate changes its trend based on a complete sample. Monte Carlo simulations are conducted to investigate the speed of convergence of the proposed test statistic.

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Long-term Changes of Physicochemical Water Quality in Lake Youngrang, Korea

  • Bhattrai, Bal Dev;Kwak, Sungjin;Choi, Kwansoon;Heo, Woomyung
    • Korean Journal of Ecology and Environment
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    • v.50 no.1
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    • pp.169-185
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    • 2017
  • Physicochemical properties of water quality were analyzed to understand the long-term variations in Lake Youngrang from 1998 to 2015. Nonparametric statistical methods were applied to deduct correlation among water quality parameters and water quality trend. In total observations(N=64), the Secchi depth (SD) transparency showed significant positive correlation with salinity (r=0.458) and highly significant negative correlation with chlorophyll-a (r= -0.649) for p<0.0001 in two-tailed test of Spearman's rank correlation. Significant negative correlations of SD were observed with chemical oxygen demand (COD), total phosphorus (TP) and total nitrogen (TN). These correlation patterns were very similar in rainy (N=25) and non-rainy (N=39) periods too. Chlorophyll-a (Chl-a) had significant correlation with COD. Sen's slope test was performed along with Mann-Kendall trend test (significance ${\alpha}=0.05$, two-tailed) to find water quality trend. Positive trends were observed for SD and salinity with Sen's slopes 0.012 and 0.385, respectively (p<0.0001). Negative significant trends were observed for total nitrogen (TN) and Chl-a with Sen's slopes -0.02 (p<0.0001) and -0.346 (p=0.0010), respectively. Temperature, COD and phosphorus components had no trends. Carlson's trophic state index (TSI) for SD, TP and Chl-a were obtained in the ranges of 46~80, 37~82 and 39~82, respectively. Trophic index values suggest that Lake Youngrang was mesoeutrophic to eutrophic and there could be possibility of anoxia during the summer and dominance of blue-green algae. Excess nutrient inputs from external and internal sources were the causes of eutrophication in this lake. The findings of this study would be helpful to recognize water quality variables to manage the water body.

Long-term Trend Analysis of Major Tributaries of Nakdong River Using Water Quality Index (수질지수를 이용한 낙동강 주요 지류지천의 장기 경향성 분석)

  • Park, Jaebeom;Kal, Byungseok;Kim, Sanghun
    • Journal of Wetlands Research
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    • v.20 no.3
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    • pp.201-209
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    • 2018
  • In this study, the water quality index was calculated using the water quality monitoring data of the major tributaries of the Nakdong River and long-term trend analysis was performed to identify the tributaries requiring priority management. We used a Real-Time Water Quality Index method implemented by the Ministry of Environment. Linear regression as a parametric method and Mann-Kendall Test and Sen Slope Test as a nonparametric method were applied for the trend analysis. The water quality index of major tributaries except for Migeon2 and Seokyo2 was in the range below Fair grade and there were no significant trends for the rest of the sites except Bukan, Chennae, Hogye, Yongdeok. Therefore, in order to improve the water quality of the main stream, management of the tributaries should be preceded.

Long-Term Water Quality Trend Analysis of Lake Soyang Using Seasonal Mann-Kendall Test (계절 Mann-Kendall 검정을 이용한 소양호의 장기 수질 경향성 분석)

  • Yeom, Hojeong;An, Yongbin;Jung, Seyoon;Kim, Yoonseok;Kim, Bomchul;Hong, Eunmi
    • Journal of The Korean Society of Agricultural Engineers
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    • v.66 no.2
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    • pp.25-34
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    • 2024
  • The long-term monitoring of the Soyang Lake's water quality, covering 25% of the North Han River watershed, is crucial for effective management of both lake water quality and pollution sources in the broader region. This study utilized continuous monitoring data from the front of the Soyang Dam spanning 2003 to 2022, aiming to analyze trends and provide foundational insights for water quality management. Results revealed a slightly poor grade (IV) for total nitrogen (T-N) in both surface and mid-depth layers, indicating a need for concentrated T-N management. Trend analyses using the Mann-Kendall test and Sen's Slope depicted a decreasing trend in total phosphorus (T-P) for both layers, attributed to non-point source pollution reduction projects initiated after the Soyang Lake's designation as a pollution control area in 2007. The LOWESS analysis showed a T-P increase until 2006, followed by a decrease, influenced by the impact of Typhoon Ewiniar in that year. This 20-year overview establishes a comprehensive understanding of the Soyang Lake's water quality and trends, allowing for a seasonal and periodical analysis of water quality changes. The findings underscore the importance of continued monitoring and management strategies to address evolving water quality issues in the Soyang Lake over time.

An Improvement Method of Sound Quality of the High-speed Coastal Passenger Ship

  • Kim, Yoon-Seok;Kim, Sa-Soo
    • International Journal of Ocean Engineering and Technology Speciallssue:Selected Papers
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    • v.3 no.1
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    • pp.56-62
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    • 2000
  • The trends of recent passenger ships are becoming speedy and luxury style to enhance comfortableness in cabin. In order to meet these trend, ship designer has to improve the sound quality as well as to reduce the sound pressure level in cabins. In this paper, the trend of noise and sound quality of real high-speed coastal passenger ships are measured and analyzed, while running on their regular courses. The sound quality parameters such as loudness, roughness, fluctuation strength, and sharpness are evaluated by Zwicker loudness calculation. In addition, we try to find sensitive critical frequency band for the improving sound quality by using signal editing. Finally, the expected effective design methods are proposed to designer for the improving sound quality of passenger ships.

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Pollutants Classification based on Trend Analysis and Assessment of Water Pollutants Achievement in Subbasins of Han River Basin (한강수계 중권역별 오염물질 추세분석 및 달성도 평가를 통한 우선관리물질 선정)

  • Kim, Kyeung;Song, Jung-Hun;Lee, Do Gil;Hwang, Ha-sun;Kang, Moon Seong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.61 no.3
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    • pp.67-76
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    • 2019
  • The objectives of this study were to analyze trends of water pollutants and to evaluate the achievement of water quality standards by subbasins in the Han River. The trends of 40 water pollutants at 232 water quality measurement points were analyzed. Chemical oxygen demand (COD), Total organic carbon (TOC), Total coliforms (TC), et cetera were found to be worsening trend. For evaluation of achievement, we evaluated water quality arithmetic mean with river environment standards and human health standards at representative points of the subbasin. Biochemical oxygen demand (BOD), TOC, Total phosphorus (T-P), Fecal coliforms (FC), TC exceeded water quality standards, and water quality of human health standards was all satisfied. So, we prioritized pollutants. If pollutants exceed water quality standards or were worse, they were classified first pollutants. Although BOD and T-P are first pollutants because of water quality standards excess, they are continuously improved. Also, it is better to maintain current status because water quality management system of BOD and T-P is well prepared. Meanwhile, TOC, TC, and FC exceed water quality standards. Furthermore, they were worse gradually, but there is a lack of management systems such as water quality standards of the effluence facilities. Therefore, it is necessary to supplement the system. The results of this study can be used as primary data for the establishment of water quality standards and selection of management pollutants.

A Study on the Strategy of Products Development for Mass Housing (공동주택 상품개발 전략에 관한 연구)

  • Yang, Young-Keun
    • Journal of The Korean Digital Architecture Interior Association
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    • v.10 no.2
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    • pp.31-38
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    • 2010
  • This study is to suggest a strategy and trend of products development by major construction companies to form a trend and to set the trend in housing market through investigation about brand image campaign for TV ad, individual design items, result of products development and special plans. It is the strategy for products development of construction companies surveyed to be divided into five kinds. First, the change from in the unit to outside. Second, centralization of design powers about products development through submit and the wining of a prize in the domestic & foreign design fair to publicize a excellent quality in a roundabout way. Third, reinforcement of service for support the habitability and design manual for secure uniform quality. Forth, investment in the environment-friendly housing and new recycling energy. Fifth, reinforcement of organizational power for improving production capability.

Quality Assessment of Clothing Products Using a Fuzzy/Multi-Attribute Model (퍼지-다속성 모델을 이용한 의류품질의 감성공학적 평가)

  • 김주용;이지현
    • Science of Emotion and Sensibility
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    • v.7 no.2
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    • pp.149-155
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    • 2004
  • This research focus on analyzing the quality of clothing product in view of consumer's sensibility trend with a emphasis on measuring objective quality of pruduct. The fuzzy logic-based multi attribute model has been developed in order to evaluate the quality of clothing product. The overall quality of a clothing products can be divided into two distinct terms, product quality and brand value. Those two values are further analyzed with a relation to human sensibility.

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